Many types of communications can be performed over data networks (wireless and/or wireline networks), including electronic mail, web browsing, file downloads, electronic commerce transactions, voice or other forms of real-time, interactive communications, and others. To enable the establishment of communications sessions in a network, various control functions are deployed in the network. Some standards bodies have defined subsystems within communications networks that include such control functions. One such standards body is the Third Generation Partnership Project (3GPP), which has defined an Internet Protocol (IP) multimedia subsystem (IMS) that includes various control functions for provision of IP packet-switched multimedia services, including audio, video, text, chat, or any combination of the foregoing.
In the 3GPP2 (Third Generation Partnership Project 2) context, the equivalent of the IP multimedia subsystem is sometimes referred to as a multimedia domain (MMD) network. In the wireline context, the equivalent of an IP multimedia subsystem is sometimes referred to as a Next Generation Networks (NGN).
Services of a packet-switched services network (e.g., IMS network, MMD network, or NGN network) may be accessed by mobile users. A mobile user may be located in a home or small business environment (“local premises”). To access an external network such as the packet-switched services network, the mobile user connects through a wireless “home gateway” in the local premises. In one example, wireless home gateways can be femtocell base stations.
The wireless home gateways may be part of a wireless access network that the mobile user is a subscriber of. In some cases, the wireless access network is a legacy circuit-switched wireless access network, such as a CDMA (Code Division Multiple Access) 1xRTT network. Because of the substantial investment by service providers in legacy circuit-switched wireless access networks, it is expected that it will be some time before service providers will be able to completely transition to packet-switched wireless access networks.
Before service can be provided to a mobile user, the mobile user has to be first authenticated. However, authentication in the context where a subscriber of a legacy circuit-switched network is attempting to access services of a packet-switched services network raises several issues. Typically, each of the circuit-switched wireless access network and packet-switched services network is associated with its respective separate authentication infrastructure. Current standards call for modification of the packet-switched services network to support authentication of mobile users that are subscribers of circuit-switched wireless access networks. Also, to support authentication by the packet-switched services network, authentication credentials maintained by the circuit-switched wireless access network may have to be copied into the authentication infrastructure of the packet-switched services network. If a service provider of the circuit-switched wireless access network has a large number of subscribers (e.g., hundreds of thousands or millions of subscribers), copying authentication credentials from the circuit-switched wireless access network to the packet-switched services network can be very inefficient. Moreover, having to maintain authentication credentials in two different networks raises the challenge of having to maintain synchronization of the copies of the authentication credentials. Also, having to modify the infrastructure of the packet-switched services network for the purpose of authenticating subscribers of legacy circuit-switched wireless access networks adds unnecessary complexity and cost.